Device and method for antenna impedance matching

• US 9,640,863 B2
• Filed: 03/01/2011
• Issued: 05/02/2017
• Est. Priority Date: 12/29/2010
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Shen, Shaowu
• Primary Examiner(s): Levi, Dameon E
• Assistant Examiner(s): Davis, Walter
• Application Number:
  US13/977,231
• Publication Number:
  US 20130271342A1
• Time in Patent Office: 2,254 Days
• Field of Search: 343861
• CPC Class Codes: H01Q 1/50 Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H

Abstract

The disclosure provides a device and a method for antenna impedance matching. The device comprises an application detection module, configured to detect a current state of an antenna of a terminal, and output a matching adjustment signal according to the state; an adaptive control module, configured to perform control over a process of matching adjustment in response to the matching adjustment signal; and a matching adjustable module, configured to, under control of the adaptive control module, perform matching adjustment on impedance of the antenna through an impedance matching network corresponding to the matching adjustment signal. Through the technical solution provided by the disclosure, the problem of single impedance matching mode in the prior art is solved, and further, the effect that differential matching can be performed for various application states of the terminal is achieved.

Claims

1. A device for antenna impedance matching, comprising:

an application detection module, configured to detect a current state of an antenna of a terminal, and output a matching adjustment signal according to the state;

an adaptive control module, configured to perform control over a process of matching adjustment in response to the matching adjustment signal;

a matching adjustable module, configured to, under the control of the adaptive control module, perform the matching adjustment on impedance of the antenna through an impedance matching network corresponding to the matching adjustment signal;

a feedback coupling module, configured to sample a matched impedance value to obtain a circuit measurement value, and output the circuit measurement value to a matching comparison module;

the matching comparison module, configured to perform a matching comparison between the circuit measurement value and a target characteristic impedance value, and feed a matching comparison result back to the adaptive control module;

wherein the application detection module comprises;

a proximity sensing unit, configured to sense a hand of a person, the head of the person and a free space, and output a sensing result to an application detection unit;

a state sensing unit, configured to sense a posture of the terminal and a use orientation of the terminal, and output a sensing result to the application detection unit, wherein the posture comprises opening, closing, slide-up, slide-down, side slide and rotation;

a user interaction unit, configured to output a setting result to the application detection unit in response to setting of a working state of the terminal by a user; and

the application detection unit, configured to output the matching adjustment signal according to the sensing result output by the proximity sensing unit, the sensing result output by the state sensing unit and the setting result output by the user interaction unit;

wherein the adaptive control module is further configured to, in response to the matching adjustment signal output by the application detection module, control the matching adjustable module to perform the matching adjustment until full matching is achieved according to a preset digital voltage mapping table and the matching comparison result fed back by the matching comparison module;

wherein the matching comparison module comprises;

a matching optimization unit, configured to provide a shortest matching adjustment path, which is able to achieve full matching, according to a preset matching curve graph.

2. The device according to claim 1, wherein

the proximity sensing unit is configured to sense the hand of the person, the head of the person and the free space through a proximity sensor by using a proximity sensing principle;

and

the state sensing unit is configured to sense the posture of the terminal and the use orientation of the terminal through a hall switch and a triaxial acceleration controller.

3. The device according to claim 1, wherein a type of the impedance matching network in the matching adjustable module comprises at least one of the followings:

π

type, T type, L-C type and C-L type.

4. The device according to claim 3, wherein the impedance matching network comprises:

a Micro Electro Mechanical System (MEMS) variable capacitor, and/or a surface micromachining suspended inductor.

5. The device according to claim 1, wherein the feedback coupling module comprises at least one of the following units:

a direct sampling unit, configured to directly sample an impedance value from an output signal of the matching adjustable module and a signal output to a feeding end of the antenna; and

an indirect sampling unit, configured to sample an antenna matching section reflected signal power, a voltage standing wave ratio or an emission coefficient which are capable of indirectly reflecting an impedance value.

6. The device according to claim 5, wherein the matching comparison module comprises at least one of the following units:

a direct comparison unit, configured to perform the matching comparison between the impedance value obtained by sampling of the direct sampling unit and the target characteristic impedance value, and feed a matching comparison result back to the adaptive control module; and

an indirect comparison unit, configured to perform the matching comparison between the voltage standing wave ratio obtained by sampling of the indirect sampling unit and a preset threshold value, and feed a matching comparison result back to the adaptive control module.

8. The device according to claim 1, wherein the application detection module comprises:

a proximity sensing unit, configured to sense a hand of a person, the head of the person and a free space, and output a sensing result to an application detection unit;

a state sensing unit, configured to sense a posture of the terminal and a use orientation of the terminal, and output a sensing result to the application detection unit, wherein the posture comprises opening, closing, slide-up, slide-down, side slide and rotation;

a user interaction unit, configured to output a setting result to the application detection unit in response to setting of a working state of the terminal by a user; and

the application detection unit, configured to output the matching adjustment signal according to the sensing result output by the proximity sensing unit, the sensing result output by the state sensing unit and the setting result output by the user interaction unit.

9. The device according to claim 8, wherein the proximity sensing unit is configured to sense the hand of the person, the head of the person and the free space through a proximity sensor by using a proximity sensing principle;

and

the state sensing unit is configured to sense the posture of the terminal and the use orientation of the terminal through a hall switch and a triaxial acceleration controller.

10. The device according to claim 1, wherein a type of the impedance matching network in the matching adjustable module comprises at least one of the followings:

π

type, T type, L-C type and C-L type.

11. The device according to claim 10, wherein the impedance matching network comprises:

a Micro Electro Mechanical System (MEMS) variable capacitor, and/or a surface micromachining suspended inductor.

7. A method for antenna impedance matching, comprising:

detecting a current state of an antenna of a terminal, and outputting a matching adjustment signal according to the state; and

selecting an impedance matching network corresponding to the matching adjustment signal, and adjusting impedance of the antenna through the impedance matching network;

wherein detecting a current state of an antenna of a terminal, and outputting a matching adjustment signal according to the state comprises;

sensing a hand of a person, the head of the person and a free space, and outputting a sensing result;

sensing a posture of the terminal and a use orientation of the terminal, and outputting a sensing result, wherein the posture comprises opening, closing, slide-up, slide-down, side slide and rotation;

outputting a setting result in response to setting of a working state of the terminal by a user; and

outputting the matching adjustment signal according to all the sensing results;

wherein the method further comprises;

providing a shortest matching adjustment path, which is able to achieve full matching, according to a preset matching curve graph;

wherein after selecting a rational impedance matching network and adjusting the impedance matching network according to the matching adjustment signal, the method further comprises;

sampling a matched impedance value to obtain a circuit measurement value;

performing a matching comparison between the circuit measurement value and a target characteristic impedance value, and feeding back a matching comparison result; and

performing further adjustment on the impedance matching network according to the matching comparison result until full matching is achieved.